LAUSR

BACKGROUND We studied the expression of CD200 in a series of 101 patients with diagnosis of myelodysplastic syndrome (MDS), to evaluate its impact on outcome and its possible association with other known prognostic factors. MATERIAL/METHODS The CD200 was detected by flow cytometry, and the chromosome karyotypes were determined by G banding respectively. The Mann-Whitney U test was used to analyze the association among CD200 expression and clinical features. In addition, the overall survival and AML transformation of the MDS patients according to the expression level of CD200 was also explored. RESULTS Overall, the flow cytometric analyses confirmed that expression of CD200 was high in this patient cohort compared to normal BM (p<0.01). The levels of CD200 in RCUD (20.3%±4.3%), RCMD (25.0%±4.5%), RAEB-1 (39.2%±4.9%), and RAEB-2 (43.2%±5.8%) groups were obviously higher than that of RARS group (6.8%±1.7%, P<0.05). Significant differences of CD200 expression were observed in the 4 groups of MDS according to IPSS risk(P<0.01). After 45-month follow-up, Kaplan-Meier analysis of patients with MDS in our study indicated that patients with high expression level of CD200 had a shorter overall survival and a high Leukemic transformation than those with low expression (p<0.01). CONCLUSIONS In conclusion, our findings provide firstly the evidence that CD200 is up-regulated and emerging as both a prognostic factor and a potential target of novel therapeutic approaches for MDS.